Technical Report Archive and Image Library (TRAIL) - 68 Matching Results

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Standardization tests of NACA no. 1 wind tunnel

Description: The tests described in this report were made in the 5-foot atmospheric wind tunnel of the National Advisory Committee for Aeronautics, at Langley Field. The primary objective of collecting data on the characteristics of this tunnel for comparison with those of others throughout the world, in order that, in the future, the results of tests made in all the principle laboratories may be interpreted, compared, and coordinated on a basis of scientifically established relationships, a process hitherto impossible due to the lack of comparable data. The work includes tests of a disk, spheres, cylinders, and airfoils, explorations of the test section for static pressure and velocity distribution, and determination of the variations of air flow direction throughout the operating range of the tunnel. (author).
Date: January 1, 1925
Creator: Reid, Elliott G
Partner: UNT Libraries Government Documents Department

Some problems on the lift and rolling moment of airplane wings

Description: This report deals with the application of the airfoil and twisted wing theory to the calculation of the lift and rolling moment of airplane wings. Most of the results arrived at are strictly true only for wings of elliptic plan form. The investigation aims to give some indications of the accuracy with which the results can be applied to the wing forms in actual use.
Date: January 1, 1925
Creator: Scarborough, James B
Partner: UNT Libraries Government Documents Department

The influence of the form of a wooden beam on its stiffness and strength III : stresses in wood members subjected to combined column and beam action

Description: The general purpose in this study was to determine the stresses in a wooden member subjected to combined beam and column action. What may be considered the specific purpose, as it relates more directly to the problem of design, was to determine the particular stress that obtains at maximum load which, for combined loading, does not occur simultaneously with maximum stress.
Date: January 1, 1925
Creator: Newlin, J A & Trayer, G W
Partner: UNT Libraries Government Documents Department

An introduction to the helicopter

Description: It is the object of this report to review briefly the aerodynamic and construction data already available and to set forth the difficulties which must be met.
Date: January 1, 1925
Creator: Klemin, Alexander
Partner: UNT Libraries Government Documents Department

Pressure Distribution on Joukowski Wings and Graphic Construction of Joukowski Wings

Description: In the first article, in connection with a lecture on the hydrodynamic basis of flight and the potential flow about a Joukowski wing, the pressure distribution on several wings is computed and plotted. The diagrams of the pressure distributions are presented accompanied with a qualitative discussion of the pressure distribution. In the second article, the the cross-sectional outline (or profile) a Joukowski wing are plotted.
Date: October 1, 1925
Creator: Blumenthal, Otto & Trefftz, E.
Partner: UNT Libraries Government Documents Department

Calculation of wing spars of variable cross-section and linear load

Description: The calculation of wing spars of constant cross-section and load has been thoroughly treated by a large number of authors. Such is not the case,however, regarding the calculation of wing spars whose section and linear load diminish toward the ends, as in wings of trapezoidal contour and decreasing section.
Date: March 1, 1925
Creator: Kirste, Leon
Partner: UNT Libraries Government Documents Department

Preliminary investigation of the effect of a rotating cylinder in a wing

Description: Into the leading edge of a wing with arbitrary cross-section, there is introduced a cylinder, which can be rotated by an electric motor by means of a cord. Observations were made in the wind tunnel on how the lift at different wind velocities was affected by rotating this cylinder.
Date: March 1, 1925
Creator: Wolff, E B
Partner: UNT Libraries Government Documents Department

The light airplane : modern theoretical aerodynamics as applied to light airplane design with a series of charts

Description: T.M. 311 gave a short outline of modern theoretical aerodynamics as applied to light airplane design. This discussion may have been somewhat obscure to the nontechnical reader. A series of charts or curves should serve to clear up such obscurity as well as to more definitely emphasize those quantities most important for each flight characteristic.
Date: August 1, 1925
Creator: Driggs, Ivan H
Partner: UNT Libraries Government Documents Department

Strength calculations on airplanes

Description: Every strength calculation, including those on airplanes, must be preceded by a determination of the forces to be taken into account. In the following discussion, it will be assumed that the magnitudes of these forces are known and that it is only a question of how, on the basis of these known forces, to meet the prescribed conditions on the one hand and the practical requirements on the other.
Date: December 1, 1925
Creator: Baumann, A
Partner: UNT Libraries Government Documents Department

Potential flow in engine valves

Description: The extensive applicability of the hydrodynamic theory to the problems of engine construction is clearly shown in the following attempt to determine by exact methods the nature of the flow in valves under variously restricted conditions. Observation shows that two principal kinds of flow occur in simple flat-seated valves. For small valve lifts, the flow is along the horizontal wall and is therefore deflected 90 degrees, but for greater valve lifts the flow separates and forms a free stream, whose angle of deflection naturally increases with increasing lift. Both these kinds of flow can, in fact, be theoretically explained.
Date: December 1, 1925
Creator: Eck, Bruno
Partner: UNT Libraries Government Documents Department

Pitot-static tubes for determining the velocity of air

Description: On the occasion of the formulation of the rules for testing the efficiency of ventilators and compressors, experiments were instituted by the subcommittee on ventilators for the production of suitable tubes for velocity and pressure measurements.
Date: February 1, 1925
Creator: Kumbruch, H.
Partner: UNT Libraries Government Documents Department

The problem of fuel measurement : the Schiske "Konsummeter"

Description: Any measuring device, which immediately indicates the rate of fuel consumption in the desired units, has the advantage of saving considerable time and fuel, besides facilitating the adjustment of the carburetor. The Schiske "Konsummeter" (made by the "PS-Vergaser and Apparatebau A. G.") was designed from the above viewpoint.
Date: May 1, 1925
Creator: Praetorius, K. R. H.
Partner: UNT Libraries Government Documents Department

Latecoere Air Lines

Description: This article presents the observations of the authors on an inspection trip of the Latecoere Air Lines routes from Southern France into North Africa.
Date: August 1, 1925
Creator: Van Zandt, J Parker
Partner: UNT Libraries Government Documents Department

Wire suspensions in wind tunnel experiments

Description: The elimination of the rigid supports for models and their replacement by wires constitute a great improvement by rendering negligible the interactions of support. There are disadvantages to wire, namely, the aerodynamic resistance is very large and their use is rather difficult because the whole suspension lacks rigidity and easily becomes distorted. We will here investigate the nature of these distortions, evaluate the errors they entail and describe the methods for taking account of or avoiding them.
Date: December 1, 1925
Creator: Kerneis, Jean
Partner: UNT Libraries Government Documents Department

A method for the direct determination of wing-section drag

Description: In order that the method may be more easily understood, we will first consider the simpler case when there is no lift, but only drag, and when the streamlines at the measuring point behind the obstacle are nearly parallel. Moreover, the flow is assumed not to deviate much from the two-dimensional flow.
Date: November 1, 1925
Creator: Betz, A
Partner: UNT Libraries Government Documents Department

Theory of flapping flight

Description: Before attempting to construct a human-powered aircraft, the aviator will first try to post himself theoretically on the possible method of operating the flapping wings. This report will present a graphic and mathematical method, which renders it possible to determine the power required, so far as it can be done on the basis of the wing dimensions. We will first consider the form of the flight path through the air. The simplest form is probably the curve of ordinary wave motion. After finding the flight curve, we must next determine the change in the angle of attack while passing through the different phases of the wave.
Date: October 1, 1925
Creator: Lippisch, Alexander
Partner: UNT Libraries Government Documents Department

Nonmetallic diaphragms for instruments

Description: This report, the second of a series of reports relating to the general subject of instrument diaphragms. The first report of the series was published as Technical Report no. 165, "diaphragms for aeronautic instruments," and comprised an outline of historical developments and theoretical principles. The present report relates entirely to nonmetallic diaphragms, the use of which in certain types of pressure elements has been increasing for some time. Little, if any, information has been available to aid the designer of instruments using this form of pressure element. It was to attempt to meet the need for such information that the investigation reported in this paper was undertaken. The report describes the various materials which have been used as nonmetallic diaphragms, discusses the factors which affect the performance of the diaphragms and gives the results of tests made for the purpose of investigating the effect produced by these factors.
Date: January 1, 1925
Creator: Eaton, H N & Buckingham, C T
Partner: UNT Libraries Government Documents Department

Pressure distribution over the wings of an MB-3 airplane in flight

Description: This investigation was carried out to determine the distribution of load over the wings of a high speed airplane under all conditions of flight. In particular it was desired to find the pressure distribution during level flight, over the portions of the wings in the slipstream and, during violent maneuvers, over the entire wing surface. The method used consisted in connecting a number of holes in the surface of the wings to recording multiple manometers mounted in the fuselage of the airplane. In this way simultaneous records could be taken on all of the holes for any desired length of time. (author).
Date: January 1, 1925
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department

Elements of the Wing Section Theory and of the Wing Theory

Description: This report contains those results of the theory of wings and of wing sections which are of immediate practical value. They are proved and demonstrated by the use of the simple conceptions of "kinetic energy" and "momentum" only, familiar to every engineer; and not by introducing "isogonal transformations" and "vortices," which latter mathematical methods are not essential to the theory and better are used only in papers intended for mathematicians and special experts.
Date: January 1, 1925
Creator: Munk, Max M.
Partner: UNT Libraries Government Documents Department

Law of similitude for the surface resistance of lacquered planes moving in a straight line through water

Description: The proof of the validity of the Reynolds law of similitude for the surface resistance of planes has been developed with an accuracy hitherto unattained and for a large range of lengths and speeds. It has been shown that, in addition to the form resistance, the resistance of the longitudinal edges must be taken into account.
Date: April 1, 1925
Creator: Gebers, Friedrich
Partner: UNT Libraries Government Documents Department